US4041691A - Electronic timepiece battery monitoring circuit - Google Patents

Electronic timepiece battery monitoring circuit Download PDF

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Publication number
US4041691A
US4041691A US05/641,046 US64104675A US4041691A US 4041691 A US4041691 A US 4041691A US 64104675 A US64104675 A US 64104675A US 4041691 A US4041691 A US 4041691A
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battery
power source
voltage
electronic timepiece
timekeeping
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US05/641,046
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English (en)
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Hiroyuki Chihara
Yasushi Okada
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Suwa Seikosha KK
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Suwa Seikosha KK
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    • G—PHYSICS
    • G04—HOROLOGY
    • G04C—ELECTROMECHANICAL CLOCKS OR WATCHES
    • G04C10/00—Arrangements of electric power supplies in time pieces
    • G04C10/04—Arrangements of electric power supplies in time pieces with means for indicating the condition of the power supply

Definitions

  • This invention is directed to an electronic timepiece battery monitoring circuit, and in particular to utilizing the voltage discharge characteristic of a battery to detect the impending failure thereof.
  • silver or mercury batteries have been the most commonly used power source in small sized electronic timepieces.
  • silver and mercury batteries are capable of driving an electronic wristwatch at a predetermined voltage level over a considerable period of time, when the battery begins to fail, the voltage delivered thereby is dramatically reduced in a short amount of time. Accordingly, the rapid drop in voltage renders it extremely difficult to monitor the impending failure of such batteries and hence makes it difficult to replace the battery prior to the failure of same. Accordingly, a battery monitoring circuit wherein the period of time over which a power source deliverying voltage to timekeeping circuitry can be sufficiently increased to provide sufficient time to effect a replacement of the power source is desired.
  • an electronic timepiece battery monitoring circuit wherein the battery's voltage discharge characteristic is utilized to detect the impending failure thereof.
  • the electronic timepiece includes a display device for displaying time in response to timekeeping signals applied thereto and for indicating a voltage level representative of impending failure of the electronic timepiece power source in response to an indication signal applied thereto.
  • An electro-chemical power source is utilized for delivering at least two characteristic voltage levels, the first voltage level corresponding to a first plateau of discharge and the second voltage level corresponding to a last plateau of discharge being sustained essentially at the second level voltage for a predetermined interval of time.
  • a battery detecting circuit is adapted to detect the second voltage level and apply an indication signal to the display device. Timekeeping circuitry in response to being energized at both characteristic voltage levels applies timekeeping signals to the display device.
  • a further object of the instant invention is to provide an electronic timepiece battery monitoring circuit wherein a battery is able to sustain a plateau of discharge at a reduced voltage level over an interval of time sufficient to provide for replacement of the battery prior to the ultimate failure of same.
  • Still a further object of the instant invention is to provide an improved battery monitoring circuit for an electronic timepiece wherein a volatile semi-conductor memory can be utilized, and the battery for energizing same can be replaced without any loss of the contents stored in the memory.
  • FIG. 1 is a graphical illustration of the discharge characteristic of a silver battery and mercury battery, respectively, constructed in accordance with the prior art
  • FIG. 2 is a graphical illustration of two-stage voltage characteristics for batteries constructed in accordance with the instant invention
  • FIG. 3 is a block circuit diagram of an electronic timepiece battery monitoring circuit constructed in accordance with the instant invention.
  • FIG. 4 is a graphical illustration of the voltage level delivered by the battery in the battery monitoring circuit depicted in FIG. 3;
  • FIG. 5 is a detailed circuit diagram of the battery voltage detecting circuit depicted in FIG. 3.
  • FIG. 1 wherein the voltage discharge characteristic of a silver battery, depicted as curve 1, and a mercury battery, depicted as curve 2, are illustrated.
  • the period Td for displaying the rapid decrease in the voltage level at the end of the battery life is very short.
  • the time over which the sudden decrease in potential can be monitored is further diminished. For example, in an electronic timepiece driven by a silver battery, once the voltage delivered by the battery falls below 1.2 volts, the electronic timepiece is no longer energized.
  • the voltage delivered falls to a level of 1.45 volts, at which same is first detected by a battery detecting circuit, the period over which the impending failure of the battery can be measured, until same falls below 1.2 volts would be on the order of two days when the current consumption of the electronic timepiece circuitry is of the order of 10 ⁇ A.
  • the instant invention avoids the difficulties noted above with respect to conventional mercury and silver batteries by providing a cell or battery, that is, an electro-chemical power source, having a discharge characteristic including at least two-stages or plateaus, the voltage level at both plateaus being sufficient to effect driving of the electronic timepiece circuitry, the last plateau being sustained over an extended period of time to provide a period Td for displaying the state of the battery just prior to the failure of same over a period ranging from one week to several months.
  • Curves 5 and 6 represent discharge characteristics of a silver battery and mercury battery, wherein the voltage level is abruptly lowered to 0.1 V to 0.5 V from the first normal operating voltage plateau to a further voltage plateau, wherein the voltage level is sustained until the failure of the power cell results in a sudden drop. Accordingly, the heavy line portions 7 and 8 of curves 5 and 6 illustrate the period Td over which the impending failure of the battery can be displayed. As is readily apparent from FIG. 2, difficulties heretofore encountered caused by variations in the voltage at which the voltage detection circuit was able to detect impending failure of the battery are eliminated by merely selecting a detection voltage somewhere between the respective first and last plateaus.
  • electro-chemical cell or battery there are several different ways to produce an electro-chemical cell or battery (the respective terms cell, battery and electro-chemical power source being utilized interchangably herein for purposes of describing either an electrochemical cell or battery formed by a plurality of cells for use in energizing an electronic wristwatch) having the two-plateau discharge characteristic illustrated in FIG. 2. It should be noted that the voltage, E, of the power source, under the use conditions considered herein, will be close to the open circuit voltage since the rate of discharge is extremely low.
  • a preferred method for forming a power source to obtain a two-plateau discharge curve is the use of different electrode materials in one of the electrodes of the cell.
  • the electrode material which provides the higher voltage is exhausted, the other electrode material will begin to function and deliver a lower voltage.
  • a suitable combination is silver oxide or nickel oxide as the positive electrode and a mixture of cadmium and zinc as a negative electrode.
  • from 80 to 95% of the negative electrode capacity could be in the form of zinc and from 5% to 20% in the form of cadmium.
  • the capacity of the positive electrode should be sufficient to discharge both the zinc and the cadmium in the negative electrode.
  • the reaction of the positive electrode of the silver oxide-zinc cell is as follows: Ag 2 O + H 2 O + 2e - ⁇ 2Ag + 20H - .
  • the electromotive force, EMF, of this reaction is 0.34V against an arbitrary standard.
  • the reaction at the negative electrode is Zn + 2OH - ⁇ ZnO + H 2 O + 2e - .
  • the EMF for the zinc electrode against the same arbitrary standard is 1.24V. Accordingly, the sum of the two electrode potentials is the EMF of the entire cell and is therefore 1.58V.
  • the silver oxide will discharge against the cadmium, giving a voltage which is about 0.45V lower, the discharge curve having the same form as that illustrated in FIG. 2.
  • the length of time during which the power source would provide the lower voltage would be ample for effecting replacement of the power source in the electronic timepiece. It is further noted that if more than two metals are combined in the negative electrode, more than two voltage levels or plateaus would be obtained. It is further noted that the same effect can be obtained by using a combination of metal oxides in the positive electrode. Such a combination could be nickel oxide with silver oxide or with mercuric oxide.
  • a further method of obtaining a two-level discharge characteristic is through control of the relative quantities of electrochemically-active materials in the respective electrodes.
  • the quantity of zinc in the negative electrode may, deliberately, be made less than the stoichiometric quantity in the positive electrode. Cells are conventionally constructed in this fashion in order to avoid leakage of the electrolyte. Conversely, if the quantity of zinc in the negative electrode is greater than that needed to discharge the silver oxide in the positive electrode, the two-level discharge curve shown in FIG. 2 can be obtained.
  • the reason for this type of discharge can be seen by referring to the analysis of the electro-chemical reactions occurring in cell being the same as those detailed above for the preferred example. Accordingly, the sum of the two electrode potentials is the EMF of the entire cell and as noted above is 1.58V. If the quantity of zinc is increased in order to obtain the two-level discharge characteristic illustrated in FIG. 2, the silver oxide in the positive electrode will be exhausted first with the result that the EMF of the cell will then be only 1.24V, the EMF of the negative electrode alone. As the discharge proceeds, the zince is eventually exhausted, at which point the cell voltage drops suddenly and the display of the second or last stage of the power cell characteristic is terminated.
  • a third technique for obtaining the discharge characteristic illustrated in FIG. 2 is to connect several cells in series and provide one of the cells with a capacity (in terms of ampere-hours) lower than the other cells. For example, if three conventional silver oxide-zinc cells are connected in series, and one of the cells has a capacity which is 80% of the others, then the battery voltage will be suddenly lowered from 4.74V to 3.50V when 80% of the rate of capacity (of the larger cells) has been exhausted. For the remaining 20% of the rate of capacity, the battery voltage will then be 3.50V.
  • a preferred form of the silver oxide-zinc cell is one in which the silver oxide electrode is charged up to the plus 2 level.
  • the silver which initially has a valence of plus 2 is discharged from AgO to Ag 2 O which is the electrode described as usual in the conventional silver oxide-zinc cell.
  • the Ag 2 O then reacts with additional zinc as described above to give a voltage of 1.58V.
  • the drop in voltage between the two levels is almost exactly 0.3V which is very convenient for detection.
  • the capacity of the cell is almost doubled that of the conventional cell which starts out with Ag 2 O, and results in a longer lasting battery.
  • cadmium can be substituted for zinc to give a very similar two-stage discharge characteristic curve but the voltage on each of the levels is about 0.45V lower than for the corresponding level with the silver oxide-zinc cell.
  • the combination of the battery having the voltage discharge characteristic illustrated in FIG. 2 with battery detecting circuitry and electronic timepiece circuitry is particularly useful for providing an improved electronic wristwatch.
  • the battery can be replaced in sufficient time to avoid non-volatilization of the semi-conductor memory circuit.
  • the period of time for replacing the battery without permitting the memory circuit to be non-volatilized can be extended.
  • the electronic timepiece includes timepiece circuitry 19 for applying timekeeping signals to a display 30.
  • the timepiece circuitry includes a high frequency time standard and a divider circuit for producing low frequency timekeeping signals in response to signals produced by the high frequency time standard.
  • the timepiece circuitry applies timekeeping signals to an electro-mechanical transducer such as a step-motor, which step-motor in turn would be mechanically coupled to the display 30 comprised of display hands to be rotated thereby.
  • the display 30 would include a further indication means, such as an LED for providing indication of a predetermined voltage level of the battery in a manner to be discussed more fully below.
  • a further indication means such as an LED for providing indication of a predetermined voltage level of the battery in a manner to be discussed more fully below.
  • the second-hand could be advanced at two-second intervals instead of one-second intervals in the manner disclosed in U.S. Pat. application Ser. No. 562,517, filed on Mar. 27, 1975.
  • the timepiece circuitry in addition to the divider circuit would include decoder and driving circuitry for receiving the timekeeping signals and applying same to the display 30 comprised of seven-segment digital display digits.
  • appropriate timekeeping circuitry could be provided to apply a higher frequency signal to one of the seven-segment display digits in order to effect flickering of same and thereby provide an indication that the battery has been discharged to a predetermined voltage level where same should be replaced.
  • the type of displays utilized to display time and provide an indication of the battery monitoring condition are many and are noted above by way of example only for an understanding of the instant invention.
  • a battery 9 is coupled through the source drain current path of an MOS switching transistor 17 to the timepiece circuitry 19 to effect energization of the timepiece circuitry when a "0" potential is applied to the gate electrode of the MOS transistor 17. Accordingly, upon the application of a "1" potential to the gate electrode of the MOS transistor 17, an open circuit is defined between the battery 9 and the timepiece circuitry 19.
  • a permanent memory 10 comprised of volatile semi-conductor element is provided.
  • a battery voltage detecting circuit 18 is coupled in parallel with the battery 9 and timepiece circuitry 19 and is adapted to produce a detection signal Q 2 upon detecting a drop in the voltage level of the battery 9. Accordingly, although the memory circuit 10, battery voltage detecting circuit 18 and timepiece circuitry 19 are energized by the battery when the switching transistor 17 is in a closed state, upon opening the switching transistor 17, only the memory circuit 10 will continue to be driven by the battery 9.
  • Control of the switching of MOS transistor 17 is effected by a control circuit, generally indicated as 16, comprised of a resistor 11, capacitor 12, inverter 13, flip-flop 14 and counter 15. As is explained in greater detail below, counter 15 applies a "1" binary state signal to the switching transistor 17 in response to the battery voltage detecting circuit 18 detecting a drop in the voltage level of the battery 9.
  • point A represents the time at which the battery voltage detecting circuit 18 detects a drop in potential from the first voltage level 20 to the second voltage level 21.
  • the MOS switching transistor 17 is opened, thereby defining an open circuit between the battery 9 and the timepiece circuitry and battery voltage detecting circuit.
  • the only current consuming element remaining coupled to the battery 9 is the memory circuit 10, and in view of the small amount of current dissipated thereby, the battery is sustained at the plateau 21 until the point C where the battery 9 is replaced to provide a new voltage level 23.
  • the dotted line 22 illustrates that complete battery failure would occur if the timepiece circuitry and battery voltage detecting circuit were not decoupled from the battery 9. Accordingly, by utilizing a small capacity auxiliary battery in the wristwatch, a remote power source or a large capacitor, the frequency adjustment information stored in the volatile memory circuit 10 is preserved during changing of the battery thereby avoiding nonvolatilization of the memory circuit 10 and hence any loss of the information stored in the memory.
  • a "1" signal is applied by inverter 13 to the set terminal S of flip-flop 14 to thereby apply a "1" output Q to the C terminal of the counter 15 to prevent the counter 15 from counting and cause the output Q n to apply a "0" output signal Q 1 to the gate electrode of MOS transistor 17 and thereby maintain same in a closed state.
  • the battery voltage detecting circuit 18 detects the change in voltage levels and applies a "1" output signal Q 2 to the reset terminal R of flip-flop 14 to thereby change the output Q n to a "0" binary state and thereby permit counter 15 to begin counting. Accordingly, a low frequency signal produced by the timepiece circuitry is applied to the counter 15, which counter can be set to a predetermined interval of time such as several days, a month or several months, whereafter same produces a "1" output signal Q 1 for referencing the control electrode of MOS transistor to a "1" state to open same.
  • the battery voltage detecting circuit 18 and timepiece circuitry 19 are decoupled from the battery 9 until the battery is replaced at the point C, whereafter the flip-flop 14 is once again set to "1" and effects a resetting of the counter 15 to produce a "0" output.
  • the output signal Q 2 is applied through the appropriate timepiece circuitry to the display 30 for providing an indication that the battery is operating at the lower voltage level, and accordingly that replacement of the battery is required. It is further noted that the control circuit 16 and MOS transistor 17 can be easily eliminated and there would still be provided a considerably extended period of time in which to advise the user to replace the battery.
  • FIG. 5 wherein an example of a battery voltage detecting circuit particularly suitable for use with the battery monitoring circuit depicted in FIG. 3 is illustrated, like reference numerals being utilized to denote like elements illustrated in FIG. 3.
  • An N-channel MOS transistor 24 is utilized to detect the voltage delivered by the battery 9.
  • the gate electrode is referenced to the positive potential electrode of the battery and a variable resistor 25 is coupled between the drain electrode and positive potential of the gate electrode, the junction defined by the variable resistor 25 and drain electrode of MOS transistor 24 further defining the output terminal Q 2 of the battery voltage detecting circuit.
  • the resistor 25 By varying the resistor 25, the threshold voltage of the MOS transistor 24 is varied.
  • the transistor 24 As long as the battery voltage delivered is substantially higher than the threshold voltage, the transistor 24 is maintained in a closed state, whereby the output terminal Q 2 is referenced to a low or "0" potential. However, when the battery voltage approximates the threshold voltage, the transistor is opened, thereby referencing the output terminal Q 2 to the higher potential to thereby produce a "1" binary signal.
  • the interval of time over which the battery life can be monitored prior to the impending failure thereof is considerably extended thereby facilitating the replacement of the battery.
  • the lower voltage level corresponding to a plateau of discharge remains stable over a predetermined interval of time, such voltage can be sufficiently high as to continue to operate the electronic timepiece.
  • the inner impedance does not increase as the voltage is lowered, so that sufficient current can be generated to drive step-motors motors and the like.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Electromechanical Clocks (AREA)
  • Primary Cells (AREA)
  • Measurement Of Current Or Voltage (AREA)
  • Electric Clocks (AREA)
  • Tests Of Electric Status Of Batteries (AREA)
US05/641,046 1974-12-13 1975-12-15 Electronic timepiece battery monitoring circuit Expired - Lifetime US4041691A (en)

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JP49143170A JPS5169664A (en) 1974-12-13 1974-12-13 Denshidokei
JA49-143170 1974-12-13

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Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4119904A (en) * 1977-04-11 1978-10-10 Honeywell Inc. Low battery voltage detector
US4160176A (en) * 1976-08-23 1979-07-03 Kabushiki Kaisha Daini Seikosha Electronic watch
US4173756A (en) * 1976-12-11 1979-11-06 Tokyo Shibaura Electric Co., Ltd. Abnormal voltage detection circuit
US4189725A (en) * 1977-05-10 1980-02-19 Hudson Oxygen Therapy Sales Company Battery powered condition sensing and display apparatus with low battery indication
US4212158A (en) * 1978-09-29 1980-07-15 Citizen Watch Co., Ltd. Electronic timepiece
US4219999A (en) * 1977-03-03 1980-09-02 Citizen Watch Company, Limited Electronic timepiece equipped with battery life display
US4223522A (en) * 1976-02-06 1980-09-23 Citizen Watch Co., Ltd. Electronic timepiece
US4232383A (en) * 1977-04-26 1980-11-04 Kabushiki Kaisha Suwa Seikosha Electronic timepiece battery monitoring circuit
US4244039A (en) * 1977-05-06 1981-01-06 Ebauches S.A. Electro-mechanical watch
USRE30852E (en) * 1977-09-30 1982-01-19 Citizen Watch Co., Inc. Electronic timepiece
US4441825A (en) * 1975-09-08 1984-04-10 Citizen Watch Co., Ltd. Low-power integrated circuit for an electronic timepiece
US4473302A (en) * 1978-12-24 1984-09-25 Canon Kabushiki Kaisha Electronic device
US4759003A (en) * 1986-02-28 1988-07-19 Seiko Instruments Inc. Electronic analog timepiece with voltage checking function
US4805350A (en) * 1982-11-24 1989-02-21 Wiltshire Consolidated Limited Knife sharpener and scabbard
US5740132A (en) * 1994-05-13 1998-04-14 Seiko Epson Corporation Electronic timepiece and method of charging the same
WO1998033098A1 (fr) * 1997-01-23 1998-07-30 Eta Sa Fabriques D'ebauches Montre comportant des moyens de detection et de sauvegarde en cas d'insuffisance de la source d'alimentation
US5822278A (en) * 1995-05-11 1998-10-13 Seiko Epson Corporation Electronic timepiece and method of charging the same
US5889736A (en) * 1995-09-26 1999-03-30 Citizen Watch Co., Ltd. Electronic watch
US6816439B1 (en) * 1999-11-24 2004-11-09 Citizen Watch Co., Ltd. Rechargeable electronic watch and driving method of rechargeable electronic watch
US20090135678A1 (en) * 2007-11-26 2009-05-28 Em Microelectronic-Marin S.A. Electronic circuit controlling the operation of peripheral members of the watch
US20100061193A1 (en) * 2008-09-11 2010-03-11 Casio Computer Co., Ltd. Electronic timepiece
US20110026370A1 (en) * 2009-07-23 2011-02-03 Tomohiro Ihashi Chronograph timepiece
RU2744819C1 (ru) * 2018-11-02 2021-03-16 Тиссо СА Способ управления электропотреблением часов
WO2023070307A1 (zh) * 2021-10-26 2023-05-04 宁德时代新能源科技股份有限公司 电池包和用电装置

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3118100A (en) * 1963-01-02 1964-01-14 Electric Storage Battery Co Electric battery and method for operating same
US3816177A (en) * 1972-11-17 1974-06-11 Eco Control Secondary cells and batteries
US3898790A (en) * 1972-11-09 1975-08-12 Citizen Watch Co Ltd Battery-driven watch with battery consumption display alarm

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3118100A (en) * 1963-01-02 1964-01-14 Electric Storage Battery Co Electric battery and method for operating same
US3898790A (en) * 1972-11-09 1975-08-12 Citizen Watch Co Ltd Battery-driven watch with battery consumption display alarm
US3816177A (en) * 1972-11-17 1974-06-11 Eco Control Secondary cells and batteries

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4441825A (en) * 1975-09-08 1984-04-10 Citizen Watch Co., Ltd. Low-power integrated circuit for an electronic timepiece
US4223522A (en) * 1976-02-06 1980-09-23 Citizen Watch Co., Ltd. Electronic timepiece
US4160176A (en) * 1976-08-23 1979-07-03 Kabushiki Kaisha Daini Seikosha Electronic watch
US4173756A (en) * 1976-12-11 1979-11-06 Tokyo Shibaura Electric Co., Ltd. Abnormal voltage detection circuit
US4219999A (en) * 1977-03-03 1980-09-02 Citizen Watch Company, Limited Electronic timepiece equipped with battery life display
US4119904A (en) * 1977-04-11 1978-10-10 Honeywell Inc. Low battery voltage detector
US4232383A (en) * 1977-04-26 1980-11-04 Kabushiki Kaisha Suwa Seikosha Electronic timepiece battery monitoring circuit
US4244039A (en) * 1977-05-06 1981-01-06 Ebauches S.A. Electro-mechanical watch
US4189725A (en) * 1977-05-10 1980-02-19 Hudson Oxygen Therapy Sales Company Battery powered condition sensing and display apparatus with low battery indication
USRE30852E (en) * 1977-09-30 1982-01-19 Citizen Watch Co., Inc. Electronic timepiece
US4212158A (en) * 1978-09-29 1980-07-15 Citizen Watch Co., Ltd. Electronic timepiece
US4473302A (en) * 1978-12-24 1984-09-25 Canon Kabushiki Kaisha Electronic device
US4805350A (en) * 1982-11-24 1989-02-21 Wiltshire Consolidated Limited Knife sharpener and scabbard
US4759003A (en) * 1986-02-28 1988-07-19 Seiko Instruments Inc. Electronic analog timepiece with voltage checking function
US5740132A (en) * 1994-05-13 1998-04-14 Seiko Epson Corporation Electronic timepiece and method of charging the same
US5822278A (en) * 1995-05-11 1998-10-13 Seiko Epson Corporation Electronic timepiece and method of charging the same
USRE41686E1 (en) * 1995-09-26 2010-09-14 Citizen Holdings Co., Ltd. Electronic watch
US5889736A (en) * 1995-09-26 1999-03-30 Citizen Watch Co., Ltd. Electronic watch
US6144622A (en) * 1997-01-23 2000-11-07 Eta Sa Fabriques D'ebauches Watch comprising sensing and saving means in case of insufficiency of supply source
WO1998033098A1 (fr) * 1997-01-23 1998-07-30 Eta Sa Fabriques D'ebauches Montre comportant des moyens de detection et de sauvegarde en cas d'insuffisance de la source d'alimentation
US6816439B1 (en) * 1999-11-24 2004-11-09 Citizen Watch Co., Ltd. Rechargeable electronic watch and driving method of rechargeable electronic watch
US8130596B2 (en) * 2007-11-26 2012-03-06 Em Microelectronic-Marin S.A. Electronic circuit controlling the operation of peripheral members of the watch
US20090135678A1 (en) * 2007-11-26 2009-05-28 Em Microelectronic-Marin S.A. Electronic circuit controlling the operation of peripheral members of the watch
US20100061193A1 (en) * 2008-09-11 2010-03-11 Casio Computer Co., Ltd. Electronic timepiece
US8213266B2 (en) * 2008-09-11 2012-07-03 Casio Computer Co., Ltd. Electronic timepiece
US20110026370A1 (en) * 2009-07-23 2011-02-03 Tomohiro Ihashi Chronograph timepiece
US8274863B2 (en) * 2009-07-23 2012-09-25 Seiko Instruments Inc. Chronograph timepiece
RU2744819C1 (ru) * 2018-11-02 2021-03-16 Тиссо СА Способ управления электропотреблением часов
WO2023070307A1 (zh) * 2021-10-26 2023-05-04 宁德时代新能源科技股份有限公司 电池包和用电装置
US11811054B2 (en) 2021-10-26 2023-11-07 Contemporary Amperex Technology Co., Limited Battery pack and power consuming device

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Publication number Publication date
JPS5169664A (en) 1976-06-16
CH622153GA3 (de) 1981-03-31
JPS5732469B2 (de) 1982-07-10

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